Henry price ball



(No Model.)

H. P. BALL.

SAFETY PLUG.

No. 460,548. Patented Oct. 6, 1891.

UNITED STATES PATENT OEEICE.

HENRY PRICE BALL, OF BROOKLYN, ASSIGNOR TO THE EDISON GENERAL ELECTRIC COMPANY, OF NEIV YORK, N. Y.

SAFETY-PLUG.

SPECIFICATION forming part of Letters Patent No. 460,548, dated October 6, 1891.

Application filed December 1, 1890. Serial No. 373,172. (No model.)

To all whom, it may concern: with the rim or may be made separately and Be it known that I, HENRY PRICE BALL, a secured thereto. Atone or more points notches citizen of the United States, residing at Brookare cut in the underside of the rim, as clearly 5o lyn, in the county of Kings and State of New shown at i. These notches are preferably di- 5 York, have invented a certain new and useful rectly under the projections 3. 5 and G are the Improvement in Safety-Plugs, of which the metal terminals of the fuse adapted to co-opfollowing is a specification. crate with correspondingterminals in a socket The invention relates to devices commonly in which the plug is placed. To the former 55 known assafetycatchesorsafetyplugsterminal is soldered or otherwise secured a 1o thatis, to devices placedin electricalcircuitscopper or other strip 7, to which is soldered which devices are adapted to conduct a northe fusible conductor 8. Evidently the latter mal current used in the system to which they conductor might be connected directly to terare applied, but which when an abnormal minal 5. The opposite end of the conductor 6o current passes through the line and through S is connected to terminal 6 t-o complete the x5 said catches burn or melt, and thus open the circuit when the plug is placed in its socket. circuit, stopping the flow of current, and pre- Above the fusible conductor is placed a cover Venting damage to translating devices in the or diaphragm 9, which I prefer to have of circuits. flexible and transparent material, such as 65 The present invention consists in an immica, in order that it may be bent to pass n zo proved holder for the cut-outs of the character under the lugs or projections 3, and thus be described, and in the several combinations held securely in place, and so that the fusible hereinafter described and claimed. conductor may be seen without removing the In the accompanying drawings, illustrating cover. 7o the invention, Figure 1 is a plan view of the IVhen the diaphragm rests on the ledge,

z5 holder and cut-out. Fig. 2 is a side view as shown, the cup in which the fusible conthereof, and Fig. 3 is a section on line x 0 of ductor is held is tightly closed, so that dust, Fig 1 moisture, dre., will be excluded; but should It is very desirable that the fusible portion said conductor burn and volumes of gas be 75 of the cut-out should be open to inspection, generated, thepressure of the gas will raise the 5o and at the same time it should be protected movable cover, (the thickness of the cover from mechanical injury, but should not be so being less than the distance between the tightly inclosed as to confine the gases which ledge and the under side of the lugs 3,) allowmaybe formed suddenly when the fuseburns. ing gas to escape through the openings 4E 8o All these ends are attained in a very simple above described. The melted metal of the 3 5 and efficient manner in the device to be deconductorwould, however, be heldin the cup, scribed. A holder for the safety-catch illusand all danger of 'lire or accidents to persons trated is shown of proper shape to fit the welhandling the holder is avoided. known Edison socket; but it is evident that The diaphragm can readily be sprung out 85 it might equally well be adapted to lit other and a new fusible conductor put in place,

4o sockets. The body of the holder I prefer to and the diaphragm returned to position.

make of glass or hard rubber cast or molded Having thus described the invention, what into the desired shape, although other ma- I claim isterials may be employed. The body of the l. A holder for fusible conductors, consist- 9o holder is in the form of a cup having an ining of a cup-shaped body supporting said 45 ner ledge l and a rim 2. The rim has at suitconductors, a rim having lugs and notches able points projections extending inward, as below the lugs, and a cover supported below shown at 3, which may be formed integral the lugs and normally closing the body, but

movable to allow the escape of gas, substancup and the external air, substantially as detially as described. scribed. 1o

2. A holder for fusible conductors, consist- This specification signed and witnessed this ing of a cup-shaped body, a cover for the cup, 22d day of November', 1890. 5 means for holding the cover on the cup, a rim HENRY PRICE BALL.

on the cup around the cover, said rim being Witnesses: notched, whereby when the cover is raised HERBERT T. HARTMAN,

slightly a passage will be open between the CHAs. HEWITT. 

